So I'm still reading Harry Potter et la Chambre des Secrets, and I'm at the part where the Weasley brothers are throwing gnomes out of their garden. When picked up, the gnome screams "Fishmoilapaix!" Remembering from reading it in English, I believe he was saying something to the tune of "LemmeAlone!", but I'm trying to figure out what words the French version is pieced together from.

"moilapaix" sounds like "me the peace!" which I'm guessing is part of the French way of saying "Leave me alone!", but what's the "fish"?